barchartdemo4.java

在软件开发中用来绘制各种图表的源码

/* ------------------
 * BarChartDemo4.java
 * ------------------
 * (C) Copyright 2003-2005, by Object Refinery Limited.
 *
 */

package demo;

import java.awt.Color;
import java.awt.GradientPaint;

import javax.swing.JPanel;

import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.axis.NumberAxis;
import org.jfree.chart.plot.CategoryPlot;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.renderer.category.BarRenderer;
import org.jfree.data.category.CategoryDataset;
import org.jfree.data.category.DefaultCategoryDataset;
import org.jfree.ui.ApplicationFrame;
import org.jfree.ui.RefineryUtilities;

/**
 * A bar chart with only two bars - here the 'maxBarWidth' attribute in the 
 * renderer prevents the bars from getting too wide.
 */
public class BarChartDemo4 extends ApplicationFrame {

    /**
     * Creates a new demo instance.
     *
     * @param title  the frame title.
     */
    public BarChartDemo4(String title) {

        super(title);

        CategoryDataset dataset = createDataset();
        JFreeChart chart = createChart(dataset);
        ChartPanel chartPanel = new ChartPanel(chart);
        chartPanel.setPreferredSize(new java.awt.Dimension(500, 270));
        setContentPane(chartPanel);

    }

    /**
     * Returns a sample dataset.
     * 
     * @return The dataset.
     */
    private static CategoryDataset createDataset() {
        
        // row keys...
        String series1 = "First";
        String series2 = "Second";

        // column keys...
        String category1 = "Category 1";

        // create the dataset...
        DefaultCategoryDataset dataset = new DefaultCategoryDataset();
        dataset.addValue(1.0, series1, category1);
        dataset.addValue(5.0, series2, category1);
        
        return dataset;
        
    }
    
    /**
     * Creates a sample chart.
     * 
     * @param dataset  the dataset.
     * 
     * @return The chart.
     */
    private static JFreeChart createChart(CategoryDataset dataset) {
        
        // create the chart...
        JFreeChart chart = ChartFactory.createBarChart(
            "Bar Chart Demo",         // chart title
            "Category",               // domain axis label
            "Value",                  // range axis label
            dataset,                  // data
            PlotOrientation.VERTICAL,
            true,                     // include legend
            true,                     // tooltips?
            false                     // URLs?
        );

        // NOW DO SOME OPTIONAL CUSTOMISATION OF THE CHART...

        // set the background color for the chart...
        chart.setBackgroundPaint(new Color(0xBBBBDD));

        // get a reference to the plot for further customisation...
        CategoryPlot plot = chart.getCategoryPlot();
        
        // set the range axis to display integers only...
        NumberAxis rangeAxis = (NumberAxis) plot.getRangeAxis();
        rangeAxis.setStandardTickUnits(NumberAxis.createIntegerTickUnits());

        // disable bar outlines...
        BarRenderer renderer = (BarRenderer) plot.getRenderer();
        renderer.setDrawBarOutline(false);
        renderer.setMaximumBarWidth(0.10);
        
        // set up gradient paints for series...
        GradientPaint gp0 = new GradientPaint(
            0.0f, 0.0f, Color.blue, 
            0.0f, 0.0f, Color.lightGray
        );
        GradientPaint gp1 = new GradientPaint(
            0.0f, 0.0f, Color.green, 
            0.0f, 0.0f, Color.lightGray
        );
        renderer.setSeriesPaint(0, gp0);
        renderer.setSeriesPaint(1, gp1);
        
        // OPTIONAL CUSTOMISATION COMPLETED.
        
        return chart;
        
    }
    
    /**
     * Creates a panel for the demo (used by SuperDemo.java).
     * 
     * @return A panel.
     */
    public static JPanel createDemoPanel() {
        JFreeChart chart = createChart(createDataset());
        return new ChartPanel(chart);
    }
    
    /**
     * Starting point for the demonstration application.
     *
     * @param args  ignored.
     */
    public static void main(String[] args) {

        BarChartDemo4 demo = new BarChartDemo4("Bar Chart Demo 4");
        demo.pack();
        RefineryUtilities.centerFrameOnScreen(demo);
        demo.setVisible(true);

    }

}